Or as low as 
himano Dura Ace FC-R9200-P Double Power Meter – 12 Speed
- With several years of development and working closely with professional teams you can expect extreme accuracy from Shimano’s first fully integrated power meter HollowTech II 12-speed Dura-Ace chainset
- Accurately calibrated strain gauges are integrated inside both left and right crank arms, this provides a stable measurement system through rotation from both sides for extremely precise data
- +/-2% accuracy of strain gauge measured power
- Bluetooth and ANT+ with wireless firmware update and data acquisition system
- Easily rechargeable integrated battery with fully waterproof reliable electric system
- Hollow outer chainring, giving vast improvements in rigidity and increased weight savings
- The hollow outer chainring has essentially removed outer chainring flex, hugely improving shift performance making it precise even under high load
- These industry leading HollowTech II cold forged hollow crank arms have evolved to increase rigidity, reduce weight, and improve strength
- The teeth have been developed to work only in conjunction with the 12-speed chains for improved contact providing more efficiency and improved power transfer
- There is a wide range of chainring ratios and crank arm lengths available enabling customisation for all riders and racing disciplines
- HollowTech II integrated bottom bracket design uses a wider bearing placement and larger axle diameter for increased stiffness and efficiency
- Bottom bracket seal design has a minimal bearing interface gives superbly smooth rolling and increased durability
